List all users in a Google Admin Directory

google-oauth-list-users.rb

require 'google/apis/admin_directory_v1'
require 'googleauth'
require 'googleauth/stores/file_token_store'

OOB_URI = 'urn:ietf:wg:oauth:2.0:oob'
APPLICATION_NAME = 'Google Admin Directory API Ruby Quickstart'
CLIENT_SECRETS_PATH = 'client_secret.json'
CREDENTIALS_PATH = File.join(Dir.home, '.credentials',
                             "admin-directory_v1-ruby-quickstart.yaml")

def authorize
  scope =  ["https://www.googleapis.com/auth/admin.directory.user.readonly"]
  client_id = Google::Auth::ClientId.from_file(CLIENT_SECRETS_PATH)
  token_store = Google::Auth::Stores::FileTokenStore.new(file: CREDENTIALS_PATH)
  authorizer = Google::Auth::UserAuthorizer.new(client_id, scope, token_store)

  user_id = ENV['USER']
  credentials = authorizer.get_credentials(user_id)
  if credentials.nil?
    url = authorizer.get_authorization_url(base_url: OOB_URI)
    puts "Open #{url} in your browser and enter the resulting code:"
    code = gets
    credentials = authorizer.get_and_store_credentials_from_code(
      user_id: user_id, code: code, base_url: OOB_URI)
  end

  credentials
end

# Initialize the API
Admin = Google::Apis::AdminDirectoryV1 # Alias the module
service = Admin::DirectoryService.new
service.client_options.application_name = APPLICATION_NAME
service.authorization = authorize
response = service.list_users(customer: 'my_customer')

puts "Users:"
puts "No users found" if response.users.empty?
response.users.each { |user| puts "- #{user.primary_email}" }